package com.heima.app.gateway.filters;

import com.heima.app.gateway.utils.AppJwtUtil;
import io.jsonwebtoken.Claims;
import org.apache.commons.lang.StringUtils;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

@Component
public class AuthFilter implements GlobalFilter, Ordered {
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
//        1.获取request和response对象
        ServerHttpRequest request = exchange.getRequest();
        ServerHttpResponse response = exchange.getResponse();
//        2.判断是否是登录 如果是则放行
        if(request.getURI().getPath().contains("/login_auth")){
            //放行
            return chain.filter(exchange);
        }
//        3.获取token
        String token = request.getHeaders().getFirst("token");
//        4.判断token是否存在
        if(StringUtils.isEmpty(token)){
            response.setStatusCode(HttpStatus.UNAUTHORIZED);
            return response.setComplete();
        }
//        5.判断token是否有效 如果过期或者报错就结束请求返回401
        try {
            Claims claimsBody = AppJwtUtil.getClaimsBody(token);
            int status = AppJwtUtil.verifyToken(claimsBody);
            if(1 == status || 2 == status){
                //token已经过期了
                response.setStatusCode(HttpStatus.UNAUTHORIZED);
                return response.setComplete();
            }

            //请求数据的增强
            Object userId = claimsBody.get("id");

            ServerHttpRequest req = request.mutate().headers(httpHeaders -> {
                httpHeaders.add("userId", userId.toString());
            }).build();

            exchange.mutate().request(req);

        } catch (Exception e) {
            response.setStatusCode(HttpStatus.UNAUTHORIZED);
            return response.setComplete();
        }
//        6.放行
        return chain.filter(exchange);
    }

    /**
     * 用来控制过滤器执行的顺序
     *   值越小 优先级越高
     * @return
     */
    @Override
    public int getOrder() {
        return -1;
    }
}
